Geoffrey started by making his power base the citadel of Angers. Geoffrey carefully placed his loyal followers on lands surrounding the city. This was to protect his own territories.[4] The lands of the abbeys of Saint-Aubin and Saint-Serge in Angers provided revenues for his most faithful men.[4] Geoffrey told both his sons, Fulk and Maurice: "No house is weak that has many friends. Therefore I admonish you to hold dear those fideles who have been friends."[5] Geoffrey used several ways of expanding his power and control. Creating family connections was one way.[6] For example his father had controlled Nantes by marrying the widowedcountess. Geoffrey brought Nantes under control by making Count Guerech accept him as overlord.[6] For some time the counts of Maine and the bishops of Le Mans had been fighting among themselves. Geoffrey saw a way to take advantage of the situation.[7] About 971 Geoffrey secured the diocese of Le Mans for his ally and friend Bishop Seinfroy.[8] Then, in 973, Geoffrey arranged the marriage of his daughter Ermengarde-Gerberga to Conan I of Rennes, the count of Maine.[9] But rather than act like an ally Conan began to oppose Geoffrey. In 982 the two met at the first battle of Conquereuil where Geoffrey defeated Conan.[10]

Geoffrey had influence in Aquitaine through his sister Adelaide-Blanche's first marriage to the powerful baron Stephen, Count of Gevaudan and Forez. After his death the lands were ruled by his widow Adelaide-Blanche.[11] Their sons, Geoffrey's nephews, Pons and Bertrand succeeded as counts there. Geoffrey's niece, Adalmode, married Adelbert, Count of Marche and Périgord. In 975 Geoffrey had his brother Guy appointed as the Count and Bishop of Le Puy.[11] In 982 Geoffrey married his now widowed sister Adelaide-Blanche to the fifteen-year-old Louis V of France. The two were crowned King and Queen of Aquitaine.[10] But the two could not get along and the marriage failed. So did Geoffrey's plans to control Aquitaine through his young son-in-law.[10]

After the death of his first wife Adele, Geoffrey married secondly Adelaise de Châlon. By this marriage he exerted control over the county of Châlons.[6] Through the marriage of his son, Fulk III, to Elisabeth the heiress of Vendôme Geoffrey brought that county under his influence.[12] Geoffrey made his son Fulk Nerra his co-ruler just before he died while attacking the fortress of Marcon on 21 July 987.[13]

↑A marriage to a member of the Carolingianroyal family was a means of raising the status of a nobleman and his family during this time. Adalbero, the Bishop of Laon later put it very well: "What ancestry confers, no act of will can break. Noble lineages descend from royal blood. For kings and princes [alike], praise of their high qualities is fitting."[3] In the tenth century kings married Carolingian women to attach themselves to this prestigious royal family.[3] Princes and noblemen were not far behind in following this example.[3]